The brassinosteroid receptor BRI1 can generate cGMP enabling cGMP-dependent downstream signaling

Janet I. Wheeler, Aloysius Tze Wong, Claudius Marondedze, Arnoud J. Groen, Lusisizwe Kwezi, Lubna Freihat, Jignesh Vyas, Misjudeen Raji, Helen R. Irving, Christoph A Gehring

Research output: Contribution to journalArticlepeer-review

20 Scopus citations

Abstract

The brassinosteroid receptor BRASSINOSTEROID INSENSITIVE 1 (BRI1) is a member of the leucine rich repeat receptor like kinase family. The intracellular kinase domain of BRI1 is an active kinase and also encapsulates a guanylate cyclase catalytic centre. Using liquid chromatography tandem mass spectrometry, we confirmed that the recombinant cytoplasmic domain of BRI1 generates pmol amounts of cGMP per μg protein with a preference for magnesium over manganese as a co-factor. Importantly, a functional BRI1 kinase is essential for optimal cGMP generation. Therefore, the guanylate cyclase activity of BRI1 is modulated by the kinase while cGMP, the product of the guanylate cyclase, in turn inhibits BRI1 kinase activity. Furthermore, we show using Arabidopsis root cell cultures that cGMP rapidly potentiates phosphorylation of the downstream substrate BRASSINOSTEROID SIGNALING KINASE 1 (BSK1). Taken together, our results suggest that cGMP acts as a modulator that enhances downstream signaling while dampening signal generation from the receptor. This article is protected by copyright. All rights reserved.
Original languageEnglish (US)
Pages (from-to)590-600
Number of pages11
JournalThe Plant Journal
Volume91
Issue number4
DOIs
StatePublished - Jun 12 2017

Fingerprint Dive into the research topics of 'The brassinosteroid receptor BRI1 can generate cGMP enabling cGMP-dependent downstream signaling'. Together they form a unique fingerprint.

Cite this